Vehicle interior panels, such as door panels, dashboard panels, instrument panels, and headliner panels, are often formed from of a thermoplastic sheet. A grain or other texture is sometimes formed in the show surface (i.e., the exposed surface of the eventual panel that can be observed by a vehicle occupant) to provide enhanced aesthetics, such as to simulate leather. A coating may be applied to the show surface of the thermoplastic sheet and to raised portions of individual granules of the grained surface in a so-called tipping process to enhance the appearance of the surface, and in some cases to furnish surface qualities like softness and matte. The coating can be a gloss, paint, or other material. In some applications, the thermoplastic sheet is formed to its product shape by a positive thermoforming process, in which the thermoplastic sheet is heated and the side of the sheet opposite the show surface is brought into contact with a thermoforming tool surface to form the thermoplastic sheet to the desired shape. Such positive thermoforming processes can limit the sharpness or definition of features formed in the show surface.